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JJJJJ
19-08-2010, 07:09 AM
I have 2 1tb disks and 2 500 mb disks. They are connected by RAID 0. Only 2 disks show up. The other 2 are "backups". I know absolutely nothing about raid. I can't even figure out how to use the backups. In fact I have no earthly use for backups anyway.
I have partitioned C: and D: each to about 300 mb and that is all I use, In fact that is all I will ever use. I don't even know if both drives are on the same disk or what size disk they are on. I only know they are wasting power spinning away all day.
I can get into the raid setup and see an option to remove raid. BUT, what will happen if I remove it? Will C: and D: remain the same? Is there a possability that I will lose the contents of either?

In fact if any tech is living around Rotorua and would like to sort them out for me he can have 2 1tb disks for his trouble.

Don't waste your time telling me how to remove the drives. My fingers are too stiff to manipulate a screw driver and my eyes are too bad to find the screws anyway.
Jack

SolMiester
19-08-2010, 08:23 AM
Jack, RAID is a combination of drives connected to either provide fault tolerance or better speed or both...You can have 5 disks together and only have 1 logical drive show in my computer. If your PC is going fine I would worry about it, why to you want to remove them.
RAID 0 is called stripping disk and you end up with 1 logical disk spread over the combination of disks stripped together.
As there isnt really much improvement that you would notice have a stripped array, I would suggest using the 2nd of each pair as the fault tolerance drive for each array in RAID 1 which is mirror. That way if any of your drives gets a fault you can keep going..

When your PC boots up, it states what arrays you have before the operating system boots up. You should confirm the arrays and what drives are connected to what. I certainly wouldn't bother stripping 2 disks, any improvement in speed would be negligible compared to the security of having fault tolerance arrays.

In any case, changing OR removing and existing array will delete all data

MushHead
19-08-2010, 09:00 AM
Jack,

Just to expand on SolMeister's explanation. RAID 0 means that only half of your data lives on each drive of a RAID 0 pair (or array in the general case). This is to boost disk performance, as each drive only has to access half the data & the RAID firmware merges the data together. This can result in peak performance roughly doubling, as you would expect (although drive performance is only one part of the equation, so you won't see double the performance everywhere, just on some disk-bound operations).

What RAID 0 does is make it difficult to revert back to a non-RAID setup, as each drive has only half the data (and it's alternating interleaved blocks all the way through, like teeth on a zip). So turning RAID 0 off or disconnecting 1 drive of a pair isn't going to help - as SolMeister says, this will effectively delete all the data on the drives. You'd have to back up 1 RAID drive to the other, then turn off RAID on the first array, reformat as single drives, then restore to a single drive from the other array, then repeat for the second array. So it's not a trivial exercise unless you know what you're doing with the backup & restore part, especially if you don't want to reinstall & start from scratch. Easier if you just want to retain your data & you don't mind reinstalling Windows & software, but still non-trivial.

JJJJJ
19-08-2010, 07:19 PM
Thanks for the info. I think I will leave it alone.